feat: implement FlowExecutor for executing flow definitions with DAG traversal and node execution

ccw/frontend/src/App.tsx

@@ -0,0 +1,17 @@
+// ========================================
+// App Component
+// ========================================
+// Root application component with Router provider
+
+import { RouterProvider } from 'react-router-dom';
+import { router } from './router';
+
+/**
+ * Root App component
+ * Provides routing and global providers
+ */
+function App() {
+  return <RouterProvider router={router} />;
+}
+
+export default App;